Want to install a toilet in basement.Of course the drain pipe is 3" off the floor(But hey,it could be 8' so I guess I should count myself lucky!).Diameter of the pipe at that point is 4"(O.D.) and is about 4' away from where I need to do the install.Can I use a rear outlet toilet to do the job without having to build a platform?Am really trying to avoid a platform at all costs.